Vinyl monomers capable of forming side-chain liquid crystalline polymers and the resulting polymers

ABSTRACT

There is disclosed a new vinyl monomer capable of forming polymeric vesicles, micelles, monolayers, and side-chain liquid crystalline polymers. The vinyl monomer is of the formula ##STR1## wherein R 1  is substituted or unsubstituted long chain alkyl or aryl and R 2  is a hydrogen atom, alkyl, or aryl. 
     The side-chain liquid crystalline polymers can be formed by free radical polymerization or by anionic polymerizations techniques. The different reaction methods give polymers of different configuration; the anionic technique results in a polymer having a nitrogen atom in the backbone. The polymers are useful in film and fiber formation and display good toughness.

BACKGROUND OF THE INVENTION

The present invention is directed to new vinyl monomers capable offorming side-chain liquid crystalline polymers and the polymersresulting therefrom. More particularly, the invention is directed tovinyl monomers (alpha-aminopropenoic acid derivatives) of the formula##STR2## wherein R₁ is a substituted or unsubstituted long-chain alkylor aryl group and R₂ is a hydrogen atom, alkyl, or aryl group. Polymersmade from the new monomers possess side-chain liquid crystalline groupsand the polymers can be formed by either free radical polymerization orby anionic polymerization techniques.

DESCRIPTION OF THE PRIOR ART

The preparation of alpha-amnopropenoic acid derivatives having lowmolecular weight substituents attached to the carbonyl group are known;see for example U.K. Pat. No. 1,354,571. These compounds are useful asbiochemical antibiotic precursors, synthetic nucleic acid mimics, andcross-linking agents. To date, no compounds have been formed whereinlong-chain alkyl groups, i.e., those with 5 to 17 carbon atoms in thechain, are present in the locations of R₁ and R₂ in the foregoingformula.

GENERAL DESCRIPTION OF THE INVENTION

The present invention is directed to alpha-aminopropenoic acidderivatives of the formula ##STR3## wherein R₁ is substituted orunsubstituted long-chain alkyl or aryl and R₂ is a hydrogen atom, alkyl,or aryl group. Because of the amphiphilic nature of these new monomers,they are capable of forming very stable vesicles, micelles, andmonolayers that may be polymerized to give stable encapsulatedsolutions.

One method for the production of the alpha-aminopropenoic acidderivatives of the present invention is a multi-step procedure startingfrom commercially available D,L-serine wherein the serine is treated toform the hydrochloride salt (optionally esterified) which is thenreacted with an acid chloride ##STR4## to form a serine derivative ofthe formula ##STR5## which in turn is reacted to convert the serine toan alanine derivative comparable to the formula of thealpha-aminopropenoic acid derivatives of the present invention.

Another method for the production of the alpha-aminopropenoic acidderivatives of the present invention is a multi-step procedure startingfrom commercially available D,L-serine wherein the serine is treated toform the hydrochloride salt (optionally esterified) which is thenreacted with phosphorous pentachloride (PCl₅) and an acid chloride toform an alanine derivative of the formula ##STR6## which in turn isreacted to convert the beta-chloroalanine to an alanine derivativecomparable to the formula of the alpha-aminopropenoic acid derivativesof the present invention.

Polymers can be made from the monomer using either normal free radicalconditions or an anionic procedure that is described in more detailinfra.

The polymers made with the alpha-aminopropenoic acid derivatives of thepresent invention have biocompatible and/or biodegradable uses such as(i) encapsulation for controlled drug release, (ii) functional vesiclesfor antibody or antigen specific diagnostic tests, (iii) in vivo/invitro studies of the mechanism(s) of endocytosis, (iv) impact modifiersof commercial polymers, i.e., a polymeric plasticizer, and (v) monolayerand Langmuir/Blodgett film-formers which can be subsequently polymerizedand used for surface modification and coatings applications.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an S.E.M. photograph of vesicles formed by the polymerizedmonomers of the present invention and is discussed at Example 4, infra,and

FIG. 2 is a photograph of the broken vesicles of FIG. 1.

FIG. 3 is a pressure vs. area curve of the monolayer composed ofN-stearoyldehydroalanine methyl ester at the air/water interface and isdiscussed at Example 22, infra.

DETAILED DESCRIPTION OF THE INVENTION

Alpha-aminopropenoic acid derivatives of the present invention arecharacterized by the presence of a log-chain alkyl group, eithersubstituted or unsubstituted, adjacent the amide-carbonyl moiety.Representative R₁ groups include C₅ to C₂₀ alkanes, both straight andbranched chain, perfluoroalkyl, phenyl, halophenyl, and lower alkylphenyl groups. Among the alkane groups, it is preferred to use C₉ to C₁₇alkanes. Specific representative groups are C₅ H₁₁, C₉ H₁₉, C₁₃ H₂₇, andC₁₇ H₃₅ groups.

Representative R₂ groups include hydrogen, C₁ to C₁₈ alkanes, and arylgroups. The alkanes and aryl groups are similar to those shown in the R₁groups but also include lower alkyl groups such as methyl, ethyl,propyl, and butyl, either substituted or unsubstituted.

The new monomers where R₁ is C₉ to C₁₇ can form vesicles because of thepresence of both a hydrophilic end group and a hydrophobic tail(amphiphilic) which results in surfactant-like properties.

The two methods used for the production of the alpha-aminopropenoic acidderivatives of the present invention are: (i) the methyl esterificationof D,L-serine in HCl saturated methanol, with subsequent reaction withthe appropriate acid chloride, followed by dehydration of the serineresidue by a CuCl catalysed reaction with a carbodiimide and (ii) themethyl esterification of D,L-serine in HCl saturated methanol, withsubsequent reaction with phosphorous pentachloride (PCl₄) followed byreaction with the appropriate acid chloride and beta-chloro elimination(dehydrochlorination) using triethylamine base. Other lower alcohols,e.g. C²⁻⁵ -alkanols, can be used besides methanol.

In addition to the methods disclosed supra for the production of thealpha-aminopropenoic acid derivatives of the present invention, othersynthetic routes are available for the production thereof including thetreatment of alanine and cysteine. Other techniques includebeta-elimination reactions on (i) O-mesylate or O-tosylate derivativesof serine, (ii) sulfinium or sulfinyl derivatives of cysteine, (iii)cysteine reacted with silver carbonate, and (iv) N-chloro derivatives ofalanine. Also available are (v) the Hofmann degradation ofdiaminopropionyl residues, (vi) the rhenium sulfide catalyzed reactionof anhydrides with methyl-2-azidopropionate, and (vii) directdehydration of serine residues with triphenylphosphine and diethylazodicarboxylate.

The new monomers of the present invention can be polymerized using freeradical techniques and it has been found that the resulting polymer hasa structure as follows: ##STR7## where n is an integer sufficient togive the resulting product a molecular weight of about 10,000 to about14,000,000 as determined by capillary viscometry and Low Angle LaserLight Scattering [LALLS].

These polymers have been found to be soluble in a variety of organicsolvents including acetone, chloroform, 1,4-dioxane, ethyl acetate,methylene chloride, and tetrahydrofuran.

The molecular weights of the polymers prepared to date by the freeradical polymerization of the alpha-amino propenoic acid derivatives ofthe present invention range from 100,000 to 3,500,000 daltons, asdetermined by capillary viscometry and LALLS. Various peroxides and azoinitiators can be used in the free radical polymerization.Representative compounds include potassium peroxydisulfate [K₂ S₂ O₈ ],2,2'-azobis-(isobutyronitrile) [AIBN], and2,2'-azobis-(2-amidinopropane) hydrochloride [V-50]. Photoinitiatorssuch as V-50, 2,2-dimethoxy-2-phenyl acetophenone [Irgacure 651],diethoxy acetophenone [DEAP], and benzophenone can also be used.

It is also possible to form polymers from the alpha-aminopropenoic acidderviatives of the present invention by an anionic technique thatresults in a formation of polymers having the following formula:##STR8## where n is an integer sufficient to give the resulting producta molecular weight of about 10,000 to about 1,500,000 as determined bycapillary viscometry and LALLS.

It has been found that a polymer of this type is insoluble in commonorganic solvents except N,N-dimethylformamide and N,N-dimethylacetamide.The anionic polymerization technique which uses an alkyl lithium (orpotassium alkoxide) initiator is similar to the method for preparingNylon-3 from acrylamide. However, as can be seen from a review of theformula of the polymer, the carbonyl group is not within the backboneand depolymerization should not occur as readily as that for Nylon-3type polymers. The polymers made by anionic polymerization techniquesrepresent a new class of polymer containing a single nitrogen in therepeating unit with functional side groups and without the associatedbackbone carbonyl found in conventional polyamides.

The polymers of the present invention, including those prepared by freeradical and anionic techniques, are new thermoplastic polymers having ahigh melting point and good toughness. The polymers can be used for bothfilms and fiber formation.

Polymerization of the monomer by either of these techniques usuallytakes place for a period of seconds (anionic) to greater than four hours(free radical) at a temperature in the range from about room temperatureto about 100° C., and at atmospheric pressure. It is preferred toundertake the polymerization for a period of up to 24 hours attemperatures between 60° C. to 100° C. (for both techniques) and atatmospheric pressure.

The following examples are representative of the invention.

EXAMPLE 1

The first method for monomer synthesis was accomplished by adaptingpublished methods for the methyl esterification, N-acylation, anddehydration of D,L-serine to form N-alkanoyldehydroalanine methyl ester[methyl N-alkanoyl-alpha-aminopropenoate]. Commerical D,L-serine wasreacted with excess HCl saturated methanol at 40° C. for 4 hours. Aftersolvent removal under reduced pressure, and vacuum oven drying, theD,L-serine methyl ester hydrochloride salt was dissolved in a mixture ofexcess chloroform and two molar equivalents of triethylamine. Whilestirring constantly at 5° C., the appropriate acid chloride was addeddropwise over a period of 4 hours. The clear solution so obtained wasallowed to stir at 5° C. overnight to complete the reaction. Thesolution was extracted once with 0.1 N HCl and again with an equalvolume of pure water to remove the triethylamine hydrochloride salt. Thechloroform phase was evaporated under reduced pressure to obtain a clearoil. In some cases, depending upon the length of R₁, the oilcrystallized on standing at room temperature. The material so obtainedwas dissolved in excess methylene chloride to which was added 10% molarexcess N,N-diisopropylcarbodiimide and 4% molar CuCl catalyst, and washeld at 30° C. for at least 4 days or until the reaction was complete(as determined by capillary gas chromatography using a 25 meter SE-54fused silica column with flame ionization detection). The suspension wasfiltered to remove the crystalline N,N-diisopropylurea side product.Solvent removal from the filtrate resulted in a green oil. Purificationwas accomplished by preparative column chromatography using a silicagel-methylene chloride system. Solvent removal resulted in a clear oilwhich was the N-alkanoyldehydroalanine methyl ester [methylN-alkanoyl-alpha-aminopropenoate]. The advantage of this method is thatthe CuCl catalyst also inhibits spontaneous polymerization. Adisadvantage of this method is the difficulty in purification for theremoval of the copper salts formed in the reaction.

EXAMPLE 2

Using the method described in Example 1, n-hexanoyl choride [C₆ H₁₁ OCl]was used to obtain N-hexanoyldehydroalanine methyl ester [methylN-hexanoyl-alpha-aminopropenoate] as a clear yellow oil which wasfurther purified by crystallization in isomeric hexanes at -40° C.

EXAMPLE 3

Using the method described in Example 1, n-decanoyl chloride [C₁₀ H₁₉OCl] was used to obtain N-decanoyldehydroalanine methyl ester [methylN-decanoyl-alpha-aminopropenoate] as a clear oil which was furtherpurified by crystallization in isomeric hexanes at -40° C.

EXAMPLE 4

Using the method described in Example 1, n-myristoyl chloride [C₁₄ H₂₇OCl] was used to obtain N-myristoyldehydroalanine methyl ester [methylN-myristoyl-alpha-aminopropenoate] as an off-white mass which wasfurther purified by crystallization in isomeric hexanes at -40° C.

EXAMPLE 5

Using the method described in Example 1, n-stearoyl chloride [C₁₈ H₃₅OCl] was used to obtain N-stearoyldehydroalanine methyl ester [methylN-stearoyl-alpha-aminopropenoate] as a white mass which was furtherpurified by crystallization in isomeric hexanes at -15° C.

EXAMPLE 6

The second method for monomer synthesis was accomplished by adaptingpublished methods for the methyl esterification, beta-chlorination,N-acylation, and dehydrochlorination of D,L-serine to formN-alkanoyldehydroalanine methyl ester [methylN-alkanoyl-alpha-aminopropenoate]. Commercial D,L-serine was reactedwith excess HCl saturated methanol at 40° C. for 4 hours. After solventremoval under reduced pressure, and vacuum oven drying, the D,L-serinemethyl ester hydrochloride salt was added in small portions over aperiod of 2 hours to a stirred suspension of 10% molar excessphosphorous pentachloride in 2-nitropropane held at 10° C. The mixturewas left at 10° C. overnight to complete the reaction. The suspensionwas filtered and the white crystalline product [3-chloroalanine methylester hydrochloride] was rinsed with methylene chloride and anhydrousacetone. The 3-chloroalanine methyl ester hydrochloride salt was addedto excess benzene and stirred below 10° C. before adding a 1 molarequivalent of triethylamine base. Another molar equivalent oftriethylamine base and 1 molar equivalent of the appropriate acidchloride were alternately added portionwise to a well stirred suspensionover a period of 1 hour. A final equivalent of triethylamine base wasadded before the reaction mixture was brought to 40° C. for 2 hours toensure complete reaction. Alternatively, the reaction mixture was placedin a refrigerator overnight. Capillary gas chromatogrpahy was used todetermine if the reaction was complete [25M SE-54 fused silica columnwith flame ionization detection]. The suspension was filtered to removethe triethylamine hydrochloride salt and the filtrate was washed twicewith 0.1 N HCl and once with an equal volume of pure water. A pinch ofhydroquinone was added to the organic phase to inhibit polymerization.Solvent removal under reduced pressure and moderate temperature resultedin a clear oil product which was the N-alkanoyldehydroalanine methylester [methyl N-alkanoyl-alpha-aminopropenoate]. This method affords aclean product which can be easily purified by repeated coldcrystallizations from hexanes. The advantage of this method is theefficacy of the reaction(s) to obtain a pure product. The disadvantageis that the inhibitor has to be removed before polymerization can occur.

EXAMPLE 7

Using the method described in Example 6, n-hexanoyl choride [C₆ H₁₁ OCl]was used to obtain N-hexanoyldehydroalanine methyl ester [methylN-hexanoyl-alpha-aminopropenoate] as a yellow oil which was furtherpurified by crystallization in isomeric hexanes at -40° C.

EXAMPLE 8

Using the method described in Example 6, n-heptanoyl chloride [C₇ H₁₃OCl] was used to obtain N-heptanoyldehydroalanine methyl ester [methylN-heptanoyl-alpha-aminopropenoate] as a yellow oil which was furtherpurified by column chromatography using a silica gel/hexanes system. Thepurified material could not be crystallized.

EXAMPLE 9

Using the method described in Example 6, n-octanoyl chloride [C₈ H₁₅OCl] was used to obtain N-octanoyldehydroalanine methyl ester [methylN-octanoyl-alpha-aminopropenoate] as yellow oil which was furtherpurified by crystallization in isomeric hexanes at -40° C.

EXAMPLE 10

Using the method described in Example 6, n-perfluorooctanoyl chloride[C₈ F₁₅ OCl] was used to obtain N-perfluorooctanoyldehydroalanine methylester [methyl N-perfluorooctanoyl-alpha-aminopropenoate] as a yellow oilwhich was further purified by crystallization in isomeric hexanes at-20° C.

EXAMPLE 11

using the method described in Example 6, n-10-undecenoyl chloride [C₁₁H₁₉ OCl] was used to obtain N-10-undecenoyldehydroalanine methyl ester[methyl N-10-undecenoyl-alpha-aminopropenoate] as a clear oil which wasfurther purified by crystallization in isomeric hexanes at -40° C.

EXAMPLE 12

Using the method described in Example 6, n-decanoyl chloride [C₁₀ H₁₉OCl] was used to obtain N-decanoyldehydroalanine methyl ester [methylN-decanoyl-alpha-aminopropenoate] as a clear oil which was furthepurified by crystallization in isomeric hexanes at -40° C.

EXAMPLE 13

Using the method described in Example 6, n-lauroyl chloride [C₁₂ H₂₃OCl] was used to obtain N-lauroyldehydroalanine methyl ester [methylN-lauroyl-alpha-aminopropenoate] as a clear oil which was furthepurified by crystallization in isomeric hexanes at -20° C.

EXAMPLE 14

Using the method described in Example 6, n-stearoyl chloride [C₁₈ H₃₅OCl] was used to obtain N-stearoyldehydroalanine methyl ester [methylN-stearoyl-alpha-aminopropenoate] as a white mass which was furtherpurified by crystallization in isomeric hexanes at -15° C.

EXAMPLE 15

Free radical polymerizations were performed in isomeric hexanes usingAIBN initiation at 60° C. Approximately one gram of monomer wasdissolved in an isomeric mixture of hexanes (dried over 4A molecularsieves) containing about 100 mg AIBN. Dry nitrogen was passed throughthe mixture contained in a septum-capped test tube for 5 minutes. Thepolymerization tube was then placed into a constant temperature oil bathmaintained at 60° C. for at least 4 hours and up to 24 hours. Solventremoval resulted in a clear polymer which was dissolved intetrahydrofuran and reprecipitated into ice cold methanol. The polymerwas vacuum oven dried to remove traces of solvent.

EXAMPLE 16

Using the method described in Example 15, six polymerizations ofN-decanoyldehydroalanine methyl ester were performed and the polymerswere characterized by capillary viscometry and LALLS in tetrahydrofuran.The intrinsic viscosities ranged from 0.36 dl/g to 3.5 dl/g whichcorrespond to weight average molecular weights [Mw] of 100,000 to3,500,000. Polarized optical microscopy (using a controllable heatedstage) revealed a softening point at 80° C. with birefringence occurringunder slight application of pressure to the sample coverslip. Thebirefringence is charcteristic of thermotropic liquid crystllinitydisplayed by side-chain comb-like polymers. The polymer was soluble inacetone, chloroform, ethyl acetate, 1,4-dioxane, 2-propanol methylenechloride, and tetrahydrofuran. The polymer only swelled in petroleumether, methanol, ethanol, N,N-dimethyl acetamide, andN,N-dimethylformamide.

EXAMPLE 17

A 1.4 g sample of purified N-decanoyldehydroalanine methyl ester monomerwas placed into a small screw cap vial. Within 3 days, underrefrigerated conditions, the monomer had spontaneously polymerized intoa clear solid. This is indicative of vinyl monomers which canautopolymerize by a free radical mechanism. The polymer was dissolved intetrahydrofuran [THF], reprecipitated into ice cold methanol, and vacuumoven dried. The intrinsic viscosity in THF at 25° C. was 8.7 dl/g whichcorresponds to a weight average molecular weight [Mw] of 14,000,000daltons, as determined by extrapolation from the Mark-Houwink plot ofother data.

EXAMPLE 18

The anionic polymerization was performed in an isomeric mixture ofhexanes using n-butyllithium or potassium tert-butoxide as theinitiator. A clean, 120° C. oven-dried test tube was charged with about1 gram of N-decanoyldehydroalanine methyl ester and 5.0 ml isomerichexanes (dried over 4A molecular sieves). A pinch ofN-phenyl-2-naphthylamine was added (to inhibit free radicalpolymerization) and the tube was capped with a serum stopper. Drynitrogen was passed through the mixture for 5 minutes before placing inan oil bath held at 60° C. Initiation of the reaction at 60° C. wasaccomplished by using an aliquot of a commercial solution ofn-butyllithium in n-hexane, or by adding crystals of potassiumtert-butoxide. The hydrogen transfer polymerization resulted in apolymer that immediately precipitated from the reaction medium. Thepolymer was insoluble in the more common organic solvents except forN,N-dimethyl formamide (DMF) and N,N-dimethylacetamide (DMAC). Thepolymerization is similar to that of the anionic method used to prepareNylon-3 from acrylamide; cf, V. R. Pai Verneker et al., Poly. Comm.,25(12), p. 363 (1984) and the references cited therein. However, sincethe carbonyl functional group is not within the backbone,depolymerization should not occur as readily as that for the Nylon-3type polymers. This is the first example of a new class of polymers thatcontain a single nitrogen in the repeat unit without the associatedbackbone carbonyl found in all polyamides. This polymer also has areactive carboxylate moiety adjacent to the main chain, as well asanother carbonyl connected to the backbone nitrogen.

Anionic solution polymerization occurred via a new hydrogen transfermechanism to give a new class of polymers with backbone nitrogen(similar, but different from polyethyleneimines, which do not have dualfunctionality). One possible mechaism is as follows: ##STR9## Thispolymer was soluble only in DMAC and DMF in contrast to the polymerobtained free radically which was soluble in many organic solvents. Inadditon, the polymer formed by anionic solution polymerization displayedlyotropic crystalline behavior in concentrated DMAC solutions. Theliquid crystllinity observed under polarized optical microscopy isprobably due to side-chain order.

Polarized optical microscopy of a concentrated solution of theanionically derived polymer in DMAC indicated lyotropic liquidcrystallinity. Also, evidence for high crystallinity in a solution-drawnfiber indicates the possibility for processing from solutions.

EXAMPLE 19

The monomers of Examples 3 and 5 also exhibited amphiphilic behavior informing stable vesicles at 1-5% by weight in water after sonication.Radical polymerization of these vesicles gave stable spheres. Infraredspectroscopic analysis of the polymerized vesicles suggests a polymerconfiguration similar to that obtained by the normal free radicalsolution polymerization.

EXAMPLE 20

The formation of vesicles was accomplished by sonication of a 1 to 5%aqueous suspension of N-decanoyldehydroalanine methyl ester at roomtemperature for one hour. Stable vesicles were formed (liposomes) asobserved by optical microscopy. A thermal, water-soluble initiator(potassium peroxydisulfate) was added to the aqueous suspension andresonicated for one-half hour. Polymerization was effected at 60°overnight to form spheres with an average diameter of 1.04 microns. Forcomparison, this is about 1/6 the size of normal human red blood cells(7.5 microns). A sample of the vesicles was melted on a microscope slideand the resulting polymer mass showed the same birefringent behavior asthe polymer obtained from the free radical solution polymerization.

A sample of the suspension was air-dried on a glass slide and coatedwith gold prior to scanning electron microscopy (SEM). The photographdepicted in FIG. 1 has a representative field at 8100X, showing almostperfect spheres with excess gold between them. The sample was thenremoved from the SEM chamber and gently scraped with a surgical knifeblade. The photograph of FIG. 2 at 8100X shows broken spheres withdistinct evidence of the hollow or "eggshell" structure.

EXAMPLE 21

The formation of vesicles was also accomplished by higher powersonication of a 1% suspension of N-stearoyldehydroalanine methyl esterin water for 30 seconds. Vesicles were formed with a greaterdistribution in size, and formation was recorded by light microscopyusing videotape equipment.

EXAMPLE 22

The formation of a monolayer of material using N-stearoyldehydroalaninemonomer was accomplished by depositing a known amount of materialdissolved in n-hexane onto the surface of pure water contained withinthe boundaries of a Lauda-Brinkman Langmuir film balance. Uponevaporation of the n-hexane, the displacement of the moveable barrierwas changed at a controlled rate to compress the monomer until collapse.FIG. 3 shows the pressure vs. area isotherm so obtained. The shape ofthe curve is typical of compounds which form stable monolayers at theair/water interface.

EXAMPLE 23

A monolayer of N-stearoyldehydroalanine methyl ester was polymerized byirradiating the monomer at the air/water interface with U.V. light (254nm). A sample of monomer dissolved in n-hexane was deposited asdescribed in Example 22. The barrier was moved in the compression modeuntil the surface pressure was 12 dynes/cm². The instrument maintainedthis pressure automatically throughout the experiment by changing thelocation of the barrier. Leaving the monlayer (without irradiation) forup to 1 hour did not reduce the area, which indicated the stability ofthe monomeric monolayer. Upon irradiation with U.V. light, an inductionperiod was followed by a measureable decrease in the total area occupiedby the monolayer. This implies that the monomer is changing from acondensed liquid/solid state to a more condensed polymeric state.Collection of the film and examination under cross polarization lightmicroscopy revealed thermal behavior similar to a polymeric samplederived from free radical solution polymerization.

SUMMARY

In summary, these examples demonstrate the novel uses of these newmonomers for the formation of:

1. new comblike polymers by radical polymerization;

2. new comblike polymers by anionic hydrogen transfer polymerizationwhich forms a new class of functional polymers;

3. aqueous polymerization to form synthetic liposomes which could haveuse in the biomedical, biochemical, and organic chemical fields; and

4. monolayers that can be polymerized by U.V. light (without the aide ofan initiator) to form a polymeric material which may have application inphotoresists, molecular wave-guide supports, and surface modification.

The vesicles capable of being formed by the monomers fo the presentinvention are believed to be filled with water although they may also becharacterized as microemulsions.

What is claimed is:
 1. A polymer containing repeating units of theformula ##STR10## wherein R₁ is selected from the group of long chainalkyl, aryl, substituted long chain alkyl, and substituted aryl, and R₂,is selected from the group consisting of a hydrogen atom, alkyl, oraryl.
 2. The polymer of claim 1 having a molecular weight in the rangeof about 10,000 to about 14,000,000.
 3. The polymer of claim 1 whereinR₁ is C₉ H₁₉ and R₂ is CH₃.
 4. The polymer of claim 1 wherein R₁ is C₅H₁₁ and R₂ is CH₃.
 5. The polymer of claim 1 wherein R₁ is C₁₃ H₂₇ andR₂ is CH₃.
 6. The polymer of claim 1 wherein R₁ is C₁₇ H₃₅ and R₂ isCH₃.
 7. The polymer of claim 1 made by a free radical polymerizationprocess.
 8. The polymer of claim 1 in the form of stable vesicles,micelles, or monolayers.
 9. A polymer containing repeating units of theformula ##STR11## wherein R₁ is selected from the group of long chainalkyl, aryl, substituted long chain alkyl, and substituted aryl, and R2,is selected from the group consisting of a hydrogen atom, alkyl, oraryl.
 10. The polymer of claim 9 having a molecular weight in the rangeof about 10,000 to about 1,500,000.
 11. The polymer of claim 9 whereinR₁ is C₉ H₁₉ and R₂ is CH₃.
 12. The polymer of claim 9 wherein R₁ is C₁₇H₃₅ and R₂ is CH₃.
 13. The polymer of claim 9 made by an anionicpolymerization process.